[PATCH AUTOSEL 4.19 068/209] ixgbe: Fix ixgbe TX hangs with XDP_TX beyond queue limit

Sasha Levin
2019-11-13T01:52:07Z

From: Radoslaw Tyl <radoslawx.tyl@intel.com>

[ Upstream commit 8d7179b1e2d64b3493c0114916486fe92e6109a9 ]

We have Tx hang when number Tx and XDP queues are more than 64.
In XDP always is MTQC == 0x0 (64TxQs). We need more space for Tx queues.

Signed-off-by: Radoslaw Tyl <radoslawx.tyl@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 14 ++++++++++----
1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
index 85280765d793d..f3e21de3b1f0b 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
@@ -3582,12 +3582,18 @@ static void ixgbe_setup_mtqc(struct ixgbe_adapter *adapter)
else
mtqc |= IXGBE_MTQC_64VF;
} else {
- if (tcs > 4)
+ if (tcs > 4) {
mtqc = IXGBE_MTQC_RT_ENA | IXGBE_MTQC_8TC_8TQ;
- else if (tcs > 1)
+ } else if (tcs > 1) {
mtqc = IXGBE_MTQC_RT_ENA | IXGBE_MTQC_4TC_4TQ;
- else
- mtqc = IXGBE_MTQC_64Q_1PB;
+ } else {
+ u8 max_txq = adapter->num_tx_queues +
+ adapter->num_xdp_queues;
+ if (max_txq > 63)
+ mtqc = IXGBE_MTQC_RT_ENA | IXGBE_MTQC_4TC_4TQ;
+ else
+ mtqc = IXGBE_MTQC_64Q_1PB;
+ }
}

IXGBE_WRITE_REG(hw, IXGBE_MTQC, mtqc);
--
2.20.1